# Codex4 vs Fluency Drop

The clearest difference is review sentiment: Fluency Drop at 83% against Codex4's 50%. Fluency Drop also leads on ratings volume (29 vs 2). Codex4's advantage is update cadence (every 4 days vs every 2 weeks) and rating (5.0 vs 4.8). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Codex4 sells 4 in-app purchases, starting at $12.99 per month and Fluency Drop sells 3 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

Codex4 holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Fluency Drop has 29 ratings behind it against 2, so its average is the more settled of the two. Written reviews complicate that: 50% of Codex4's written reviews are positive against 83% of Fluency Drop's, so the app with the better star average is not the one people write more warmly about.

Codex4 ships an update every 4 days, Fluency Drop every 2 weeks. The most recent releases landed on September 17, 2026 and September 16, 2026 respectively.

## The numbers

| Metric | Codex4 | Fluency Drop |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/codex4-for-serious-study/id6743228019/reviews)** | [4.8 (29 ratings)](https://appshunter.io/ios/app/fluency-drop-learn-languages/id6745232382/reviews) |
| Number of ratings | 2 | **29** |
| Positive reviews | 50.0% of reviews | **83.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 4 days** | Every 2 weeks |
| Monetization | Freemium | Free with in-app purchases |
| Size | 52 MB | 77 MB |
| Requires iOS | **15.6** | 16.4 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Jonas Richner](https://appshunter.io/developer/1801973188) | [Alexander Petrakis](https://appshunter.io/developer/1687941059) |

## What reviewers say

### Codex4

[App page](https://appshunter.io/ios/app/codex4-for-serious-study/id6743228019)

Build a usable vocabulary for your job, studies, or hobbies with smart, spaced repetition reviews. Master real word usage and track your progress with clear statistics. Designed for serious learners with a clean interface and no gimmicks.

**Highlights:** Add custom words from any text, Spaced repetition reviews (FSRS), Master word lemmas and conjugations, Clear progress statistics, Automatic word extraction, Data export and offline access

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Basic | $12.99 | per month |
| Pro | $14.00 | per month |
| Basic Yearly | $69.99 | per year |
| Pro Yearly | $85.00 | per year |


### Fluency Drop

[App page](https://appshunter.io/ios/app/fluency-drop-learn-languages/id6745232382)

This app offers an AI-powered approach to language learning through engaging stories and interactive exercises. It provides instant translations, grammar explanations, and personalized vocabulary review to help users achieve fluency.

**Highlights:** AI-generated stories for all levels, Instant translations and explanations, Spaced repetition flashcards, Speech practice with feedback, Supports over 30 languages, Personalized learning paths

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Monthly Subscription | $9.99 | per month |
| FluencyDrop Premium | $79.99 | per year |
| Premium Annual Subscription | $99.99 | per year |


## Frequently asked questions

### Is Codex4 free?

Codex4 is free to download, with in-app purchases available.

### Is Fluency Drop free?

Fluency Drop is free to download, with in-app purchases available.

### Which has better reviews, Codex4 or Fluency Drop?

Codex4 is rated higher. Codex4 averages 5.0 out of 5 from 2 ratings, while Fluency Drop averages 4.8 from 29 ratings.

### Do Codex4 or Fluency Drop have ads?

Neither Codex4 nor Fluency Drop shows ads.

### Which is updated more often, Codex4 or Fluency Drop?

Codex4 ships an update every 4 days, and Fluency Drop every 2 weeks. Most recently, Codex4 was updated on September 17, 2026 and Fluency Drop on September 16, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*